The number of opportunities for the use of a display apparatus, for example, a smart device typified by a smart phone, digital signage, or a window display, under strong ambient light has been increasing in recent years. In association with the increase, there has been occurring a problem such as: the reflection of the ambient light by the display apparatus itself or a reflector to be used in the display apparatus such as a touch panel portion, a glass substrate, or a metal wiring; or the reflection of a background on the display apparatus or the reflector. In particular, an organic electroluminescence (EL) panel that has started to be put into practical use in recent years is liable to cause a problem such as the reflection of the ambient light or the reflection of the background because the panel has a metal layer having high reflectivity. In view of the foregoing, it has been known that such problem is prevented by providing, as an antireflection film, a circularly polarizing plate including a retardation film (typically a λ/4 plate) on a viewer side.
Incidentally, in recent years, there has been an increasing demand for an organic EL panel that is flexible and bendable. Further, it has been demanded that the organic EL panel be not merely flexible and bendable, but be enabled to be bent with an extremely small radius of curvature. However, when the organic EL panel is bent with an extremely small radius of curvature, the retardation film of the circularly polarizing plate is subjected to a large force (partly a tensile force and partly a compressive force), resulting in a change in retardation at a portion subjected to the force. As a result, an antireflection function of the circularly polarizing plate at a bent portion is reduced, resulting in a change in color only at the bent portion, which has been recognized as a significant problem. Particularly in the case of a circularly polarizing plate including a retardation film having a reverse wavelength dispersion characteristic, although an excellent reflection characteristic is obtained, the problem of the color change due to bending is prominent.